How does VRAM allocation work in GPU(s) of those in AMD APUs?

[Ordinarily_Greater]

Hello everyone, a little thought lately about this popped up in my mind when I was observing VRAM usage in a game.

 

I have not found any info on AMD's official website about VRAM allocation in AMD APUs (laptop ones in particular), not even shared or dedicated memory details

For instance I've searched for details on Ryzen 5 5500U, about its VRAM for the built-in GPU it has and in AMD's website I haven't got that information at all

Now, I remember seeing one build guide using one of the first gen or the 2nd (3000 series) Ryzen APUs where in the BIOS it can be configured whether how much system RAM is to be assigned for use for the GPUs of these AMD APUs, I think what I saw was Tech YES City's vid on it

I think for desktop class APUs its pretty clear how they execute the GPU VRAM situation and I am sure that's the case too for the unavailable for mainstream retail Ryzen 7 4750G and ever since AMD has reestablished their APUs using Zen architecture

So yeah I wonder if there is an instance where AMD has explained this for the laptop GPU equipped chips they make

 

Thank you for your time reading this readers

Thank you for discussion contributors

[Coolmaster]

APUs don't have VRAM they solely use system RAM. In the BIOS you can reserve a certain amount of system ram to be only APU ram and how much of the system ram should be shared.

[Mark Kaine]

also u won't get a lot of info from AMD because this is controlled by the game or application,  you can only set a portion of your ram to be "gpu ram" in BIOS, usually limited to 2GB iirc.

[-rascal-]

24 minutes ago, Ordinarily_Greater said:

Hello everyone, a little thought lately about this popped up in my mind when I was observing VRAM usage in a game.

 

I have not found any info on AMD's official website about VRAM allocation in AMD APUs (laptop ones in particular), not even shared or dedicated memory details

For instance I've searched for details on Ryzen 5 5500U, about its VRAM for the built-in GPU it has and in AMD's website I haven't got that information at all

Now, I remember seeing one build guide using one of the first gen or the 2nd (3000 series) Ryzen APUs where in the BIOS it can be configured whether how much system RAM is to be assigned for use for the GPUs of these AMD APUs, I think what I saw was Tech YES City's vid on it

I think for desktop class APUs its pretty clear how they execute the GPU VRAM situation and I am sure that's the case too for the unavailable for mainstream retail Ryzen 7 4750G and ever since AMD has reestablished their APUs using Zen architecture

So yeah I wonder if there is an instance where AMD has explained this for the laptop GPU equipped chips they make

 

Thank you for your time reading this readers

Thank you for discussion contributors

 

10 minutes ago, Coolmaster said:

APUs don't have VRAM they solely use system RAM. In the BIOS you can reserve a certain amount of system ram to be only APU ram and how much of the system ram should be shared.

 

It *should* be configurable within the BIOS, HOWEVER, that setting could also be locked out.

Particularly, if it is a laptop or a pre-built PC running a custom OEM (i.e. Acer, DELL, HP, etc etc) BIOS.